Mr. Simon, who created numerous hits over his long career, has been called the most successful playwright in American theatre history.

Neil Simon

Neil Simon, the prolific playwright who produced a string of comic smashes and was the most commercially successful American playwright in the latter half of the 20th century, died August 26 at New York-Presbyterian Hospital following complications from pneumonia. He was 91 years old. He was surrounded by his wife, Elaine Joyce Simon, and his daughters, Ellen and Nancy Simon.

Most playwrights are lucky if they have one play that becomes a household name and a repertory staple. Mr. Simon had several; Barefoot in the Park, The Odd Couple, The Sunshine Boys, California Suite, and Brighton Beach Memoirs were just a selection of his many hits. He also succeeded with musicals, collaborating on Little Me, Sweet Charity, Promises, Promises, and They’re Playing Our Song.

Most of his plays were converted into films, beginning with Come Blow Your Horn in 1963. Other work adapted for the screen included Barefoot in the Park, which starred a young Robert Redford and Jane Fonda, The Odd Couple with Jack Lemmon and Walter Matthau, Sweet Charity with Shirley MacLaine, Plaza Suite, Last of the Red Hot Lovers, The Prisoner of Second Avenue, The Sunshine Boys, I Oughta Be in Pictures, and two parts of his semi-autobiographical “Eugene Trilogy”: Brighton Beach Memoirs and Biloxi Blues. (The third part, Broadway Bound, was made into a television movie.)

Simon also made his mark as a creator of original screenplays, writing the scripts for the 1972 critical hit The Heartbreak Kid, which was directed by Elaine May; The Out-of-Towners, starring Jack Lemmon and Sandy Dennis as hapless visitors comically victimized by New York City; Murder By Death, a spoof of the detective genre; and the 1977 romantic comedy The Goodbye Girl, which starred his then-wife Marsha Mason and helped to make Richard Dreyfuss a star. He was nominated for an Oscar for the latter, as well as for the films of California Suite, The Sunshine Boys, and The Odd Couple. He won a Golden Globe for The Goodbye Girl, and was nominated for The Sunshine Boys and The Heartbreak Kid.

During his heyday of the 1960s, ‘70s, and ‘80s, Simon was even more honored in the theatre. Fifteen of his plays and musicals were nominated for Tony Awards. Three won: The Odd Couple in 1965, Biloxi Blues in 1985, and Lost in Yonkers—his last big Broadway hit—in 1991. The latter also won the Pulitzer Prize for Drama that year.

Simon, along with his brother Danny, cut his teeth in the 1950s as a member of the famous crew of comedy aces that wrote for Sid Caesar’s Your Show of Shows. The staff became the stuff of legends. His colleagues included future comedy greats Mel Brooks, Carl Reiner, Woody Allen, Larry Gelbart, Selma Diamond, and Mel Tolkin. The writer’s room was a pressure cooker, but Simon thrived there. “It was probably the most enjoyable time I ever had in writing with other people,” he later said. He translated his experiences with Caesar to stage in the 1993 comedy Laughter on the 23rd Floor, in which Nathan Lane played a Caesar-like figure.

Simon worked for Your Show of Shows from 1950 to 1954 and then Caesar’s Hour from 1954 to 1957. He would later help create a musical vehicle for his former boss with Little Me, a picaresque musical in which Caesar played seven parts. The show, which ran eight months, earned Caesar his only Tony nomination.

Simon broke out of television with Come Blow Your Horn, the story of a provincial young man who is swayed by the swinging bachelor life of his older brother. The play took him three years to write, and he redrafted it at least 20 times. (It was a habit he never broke; Simon typically tinkered with his play until opening night, producing countless drafts.) Though reviews were lukewarm, the show proved a surprise hit, running 677 performances, fueled mainly by positive word of mouth and an inventive ad campaign based on New Yorker cartoons.

Robert Redford and Elizabeth Ashley in Barefoot in the Park

With Barefoot in the Park, a comedy about mismatched newlyweds, however, he broke out. The show, which starred an unknown Redford and Elizabeth Ashley under Mike Nichols' direction, ran for nearly four years. Together, Simon and Nichols helped boost each other’s stage careers. They would work together throughout the 1960s and early ‘70s on hit after hit: The Odd Couple, Plaza Suite, and The Prisoner of Second Avenue.

Among those, nothing quite out-performed The Odd Couple in recognition or endurance. The premise was simple: two divorced men, one a slob (played by Matthau on Broadway), the other a neat freak (played by Art Carney), move in together and drive each other crazy. Simon based the story on his brother Danny’s divorce. Not only did it run for more than two years on Broadway (at one point in 1966-67, Simon had four productions running simultaneously on Broadway), but it inspired a hit film starring Matthau and Lemmon, and a popular television sitcom, starring Jack Klugman and Tony Randall. It is a regular attraction on the community theatre circuit.

As Nichols became busy as a film director, Simon forged other professional partnerships. Beginning with California Suite in 1976, Gene Saks, a former actor who had directed the film versions of Barefoot in the Park and The Odd Couple, became his director of choice, staging the Eugene trilogy and Lost in Yonkers with great success. A long association with producer Emanuel Azenberg, meanwhile, began in 1972 with the hit The Sunshine Boys.

During his glory years as a playwright powerhouse, Mr. Simon also developed a reputation as a formidable, behind-the-scenes show doctor, a status borne out by his nickname “Doc.” (He actually got the nickname while in high school, but it suited his new sideline as script fixer.) One of his most notable repair jobs: the book to A Chorus Line.

In 1968, he even became a Broadway theatre owner, buying the Eugene O’Neill Theatre, and mounting many of his new plays there. He sold it in 1982.

Matthew Broderick and Elizabeth Franz in Brighton Beach Memoirs

The 1970s saw Simon broadening his range with shows such as The Gingerbread Lady (1970), starring Maureen Stapleton as a cabaret singer whose life and career are destroyed by alcohol, and The Good Doctor (1973), a series of short plays drawn from the work on Anton Chekhov. The 1980s saw the arrival of the autobiographical “Brighton Beach Trilogy,” and, with it, a return to critical favor. Critics applauded Brighton Beach Memoirs (1983), about Mr. Simon’s childhood in Brooklyn, Biloxi Blues (1985), about his tour in the Army, and Broadway Bound (1986), set at the dawning of his writing career, as heartfelt, warm and unforced in their humor. Simon’s new critical bonafides landed him on the cover of Time magazine in 1986.

All three plays had healthy runs on Broadway, with Brighton being the longest. Starring as the young Neil Simon—named Eugene Jerome—in the first two plays was Matthew Broderick. The roles launched the actor’s career, as past Simon plays had often done for other performers. The first play won Broderick a Tony Award.

Mr. Simon’s winning streak continued with Lost in Yonkers, in which tackled dramatic content with greater aplomb than he had in the past. Set in 1942, it examined the trials of two children whom their father places in the care of their stern, unforgiving grandmother. The old woman additionally has a tortured family dynamic with her two children, the savvy Louie and the challenged Bella. The show featured sterling performances by Irene Worth, Mercedes Ruehl, and Kevin Spacey. All three won Tonys, as did Mr. Simon for the play. He also won the Pulitzer Prize for Drama. The show ran two years. It would be Simon’s final Broadway hit.

His 1990s output included Jake’s Women, Laughter on the 23rd Floor, Proposals, The Dinner Party, and 45 Seconds From Broadway; the 21st century saw revivals of some of his best known works, among them The Odd Couple, Bright Beach Memoirs, Sweet Charity, and Promises, Promises.

For a writer of work that, on the surface of it, could seem so lighthearted and buoyant, Mr. Simon wrestled with assorted demons all this life. Born July 4, 1927, in the Bronx, he grew up during the Great Depression in Washington Heights. His parents, Irving Simon, a garment salesman, and Mamie (Levy) Simon, a housewife, were always financially strapped and fought often. Sometimes his father would abandon the family for weeks at a time. During such times, Simon and his brother Danny often stayed with relatives.“It was like coming from five broken families,” Simon once said. “That pain lingers. We never knew where our next meal was coming from.”

At an early age, recognizing that he had to look out for himself, he began to write. “It made me strong as an independent person,” he said. He also found refuge at the movies, where films by Charlie Chaplin and Buster Keaton inspired him to write comedy—to provoke from strangers the sort of laughter that was wanting in his home life.

Following high school, he enlisted with the Army Air Force Reserve and was stationed at Lowry Air Force Base in Denver. Beginning in 1946, he attended the University of Denver.

Having grown up poor, Simon was not always wise in money matters. In 1965, a manager persuaded him to sell the stage rights to Barefoot in the Park and The Odd Couple for $125,000. As a result, Simon never received any income on the hundreds of subsequent stagings of the plays—two of his most popular titles—or from the television series based on The Odd Couple.

Neil Simon and Elaine Joyce

"I couldn't watch the show for two years; I was so angry at myself and the business manager who persuaded me to sell the rights," he said.

Though his output slowed during the last decade of his career, his critical standing continued to rise. As critic Walter Kerr wrote, “Because Americans have always tended to underrate writers who make them laugh, Neil Simon's accomplishment have not gained as much serious critical praise as they deserve.

“His best comedies contain not only a host of funny lines, but numerous memorable characters and an incisively dramatized set of beliefs that are not without merit. Simon is, in fact, one of the finest writers of comedy in American literary history.”

In addition to his wife Elaine (the two were married in 1999) and daughters Ellen and Nancy (from his marriage to Joan Baim, from 1953 until her death in 1973), Mr. Simon is survived by daughter Bryn Lander Simon (whom he adopted) from his marriage to Diane Lander, three grandchildren, and one great-grandson.